Eye protector



' Dec. 11, 1945. H, B, L WI 2,390,599 EYE PRQTECTOR Filed March 14, 1942INVENTOR. Howmao B. L M5 251- Z M 1 m ATTORNE)? iclosure about the eyes.

Patented Dec. 11, 1945 EYE PROTECTOR Howard B. Lewis,Venice, Caliii,assignor to B. F. V

, McDonaldCompany, Los Angeles, Calif.

Application March '14, 1942, Serial No. 434,683 2 Claims (o1. 2 14) istof a nature requiring some 'formof an en- This enclosure, in order tooperate as a protector, must confront the eye -vvith a material that isvision clear and has sufficient strength to withstand the impact ofbjects that maybe encountered. Since the natures of these occupationsare hazardous in many respects, it is necessary that theprotectorprovide as wide vision as possible. The ultimate in wide visionincludes full or unobstructed binocular Vislon and complete monocularvision as Well as an ample scope of vision in a vertical direction.

A factor contributing most to limiting the field of vision islthe lenssupport provided for positioning and supp rting the lens against theface and attempts have been made to enlarge the rangeof Vision for thistype of construction by using some form of curved lens that extendsabout the face. The somewhat rigid support extending outwardly toprovide adequate spacing from the face for supporting the curved lensusually carries some form of bulky spongy or rubber ma terialcomfortable in engaging the face to lessen the discomfort causedbypressure in holding the protectors in position. Such a construction obUNITED STATES PATENT OFFICE the face and'distribut'es the pressureequally about the engaging surface Also, the Weight of the structurecontributes considerably in causing discomfort because most of theweight is supported by pressureagainst the face while the balance issupported directly by the nose; For any design of protector, weightshould be kept at :a minimum and any substantial reduction over previousstructures would be of considerable advantage.

Another factor to be cohsideredi's the reduction or elimination offogging of the lenses which is accomplished by supplying properventilation of the lens by suitable vents of minute holes or bafiledslots formed in the structure to produce a draft across the innersurface of the lens with sufficient velocity to carry any hig'hlyhumidified atmosphere out of the protector chamber into the outsideatmosphere. This means of fog elimination is limited in its capacity andmaterial selected for the'protectormust be of a nature that fogging isnot duced. I

Since eye protectors are used quite extensiveaccentuatd but, ifpossible, re-

ly in industry and even greater use is encouraged,

it is important that any improvements made in protectors be of suchnature that the assembly structs materially the field of binocularvision especially at close range, which is the field of vision that isused most in industrial applications. The construction also limitsconsiderably the extent of monocular vision.

In improving the vision of a protector, cognizance must be taken of thefact that the device must fit about the face yet be supported in somecomfortable manner from the head since comfort in wearing is ofconsiderable importance.

Ordinaryusage of the protector is continuous for periods of severalhours and even small discomfort should be avoided in initial Wearingsince this condition becomes exaggerated and unbearable after a periodof continuous use and workers are known to have preferred the hazardrather than endure the discomfort. 'I'herefora'the face enaging surfaceof the frame or lens support which directly engages the face and appliesthe support pressure to the face must be properly fitted to the subjectif the sponge or rubber cushion isto be eliminated and more visionobtained. As individual constructions are not contemplated and are notpractical for industrial applications, a universal shape must beprovided which conforms to the contour of the right and left eye socketsand which does not form pressure points about can be su pliedinexpensively and; if necessary, be repaired without muchinconvenienceand at small expense. Many other qualities must beincorporated, some of which are set forth specifically in the objects ofthe invention. From good authority, it is estimated conservatively that10% of all industrial accidents in this country concern the eye, theestimated industrial accidents in this country exceeding threemillionyearly. This condition exists in spite of the protectors available andin use and illustrates the urgent need for an improved protector whichhas all the advantages necessary so that Workers will choose to wearprotection rather than, as has been the case heretofore, have to becompelled or persuaded. r

It is aprincipal object of this invention to provide an eye protectorproviding substantially wide vision, which is comfortable to the wearer,light in weight, strong, capable of withstanding hard usage, ofnon-corrosive material which does not discolor the skin and withstandssterilization, inexpensive to manufacture, universally adaptable and.has structural characteristics to accom modate vents for substantiallyeliminating foging'of the lens.

By'using a lens having a curvature that resembles somewhat the contourof the face, certain optical errors are introduced due to thecylindrical effectof the surfaces as well as the existence of prismaticerror due to the thickness of the lens and unless the lens is properlydisposed in relation to the eye, these errors are such that they produceeye fatigue and irritation and make the protector impractical. Theoptimum in disposition of a curved lens for reducing or substantiallyeliminating the errors is to position the line of straight-ahead visionnormal to thesurface of the lens at the point of intercept. The use of aseparate support ha limited the extent of disposition of the lens aboutthe eye and al-- though certain improved relationships have been 1 ofsuch construction that the lens is properly supported from'the face anddisposed in a desirable optical relation with respect to the eye so thatsubstantially full binocular vision is obtainable while the extent ofmonocular vision is greatly increased.

It has always been thought that to comfortably seal the protector to theface, some form of rubber pad or strip mounted to the inner periphery ofthe support and having a fiat or compressible surface to engage the faceand act additionally as a cushioning means against the pressure exertedin maintaining the protector in proper position was required. Asexplained above, this form of a construction or support along with thesupporting frame or lens support obstructs the scope of visionmaterially. It has been found that a more orless rigid support oflightweight mate- Another object of this invention is to provide an eyeprotector of transparent moldable material having a lens and a supportintegral therewith which can be molded by means of the injection processin molding, which is comfortable in wearing, which has a rigid faceengaging surface at its inner extent readily sealed to the face of thewearer with the application of little rial having a. rigid face engagingsurface of a shapegenerally conforming to the curvature of the faceabout the eye and so arranged or detain individual characteristics forcomfortable sealing. I

Another. object of this invention is to provide a lightweight, widevision eye protector having a lens and frame or support of moldablematerial, the support having a surface that conforms to the face andbeing designed so that the lens is positioned in a desirable opticalrelation with respect to the eye and does not obstruct or interfere withthe full vision obtainable by virtue of the nature of the contour of thelens provided.

Another object of this invention is to provide an eye protector of anintegrally molded lens and support of transparent material in which thesupport actually forms a continuation of the lens and terminates in ashape comparable to the contour of the face with. the lens disposed inrelation to the eye to give certain desirable optical properties as wellas provide substantially full vision. r c v ment;

' Itis proposed by this invention to mold a com- -'plete eye protectorthat includes a lens of ample thickness to give adequate protection fromwhich a portion extends inwardly to form a surface that is to engage theface and space and seal the lens from the face and which can be soarranged that a lens having a certain curvature can be. positioned withrespect to the eye to provide the best availabl optical properties; Itwas thought; since such an article is to include a portion that issuitable for vision purposes, that the process of manufacture of moldedtransparent material could not be practiced in molding it withoutproducing'certain striae or blemishes in the lens and without formingweld lines in the lens surface.

Such a lens would be highly unsatisfactory since it would not havesufficient strengthte withstand the drop ball test, nor would it becapable of transmitting not less than 89% of incident visible light,whichconditions are required of a satisfactory lens. By this invention acomplete eye protector is molded and for certain curvatures the lens maybe actually disposed in such close relation to the nose that the lens.itself almost actually forms apart of the support. or a surface thatengages the'face. This. condition represents an extreme condition ofdesign-of support but is one that does give desirable results forcertain curvatures of the inside and outside surfaces defining the lensand illustrates the extent of application and accommodation of thinvention.

An important feature of this invention is that it makes .possible an'eye'proteotormade up of an integral protective lens and support of moldablematerial, the lens having a curvature whichapproaches the flat surfacebut resembles somewhat the contour of the face. The inside and outsidesurfaces of the lens have afcertain relation to provide desirableoptical properties when properly disposed. The lens and support are soformed that the optical center of the lens is coincident with the lineof straight-ahead vision when disposed on a wearer. Furthermore, theprotector do'es'not require an inconvenient or uncomfort ableconstruction of support to provide the desired disposition of lens, itdoes not interfere with the extent of vision obtainable from the lensand it provides further improvement in being light in weight, cheap,strong and has other characteristics important in protector structure.

In the drawing:

Fig. 1 is a front elevational view of the preferred embodiment inWearing position which illustrates the attachment of an adjustablebridge to each of a pair of protectors and a headband connected to thetemporal sides of each of the protectors;

Fig. 2 is a top plan view: of the same embodi- Fig. 3 is a frontelevationalview of the em- I of the lens with respect to the eye.

engaging surface 4 is shaped to fit the contour the complete protector.that little pressure need be applied to hold the temporal side;

Figs. 4 and are nasal side and temporal side views respectively;

- Fig. (his a sectional. view taken along the line unitary protectorhaving; a lens extending across the eye. to permitiull' binocular visionand a substantial. increase in monocular vision, to which is joined aframe for supporting the lens on the face which actually is an integralpart of the lens, which forms an. inward projection from the peripheraledge of the lens terminating: a surface.- that. is to. fit. the faceabout theeye and which is shaped to. generally conform tothe contour ofthe face.

Proceeding now to a detailed description ofmy invention, a preferredembodiment is shown in Figs. 1. to7, ,of the drawing in which thenumeral .1 indicates a protector made up. of a lens 2 and a frame 3which may be referred to as the; in-

wardly: extending peripheral wall of the lensand which has sufiicientdepth from the face engaging surface 4 of. the wall to convenientlyaccommodate the eye withinthe chamber 6 defined. by the"protector andto. provide optical disposition The face of the face about the eye andto conform to the face generally. It is preferred that this surface berounded or beaded. It has beenfound that, by shaping the protector toconform generally to the face, the protector is held in place by virtueof its own fit to the face and the light weightof This has the advantageprotector in place with the result that, even though the protector isused for several hours, no uncomfortable feeling or any pain about theeye or forehead occurs. It is preferred that the temporal side of thelens 2 converges into the frame or wall with the least angulardisposition 7 possible. While it would be preferred to arrange thecurvature of the lens so that it would continue to the temporal edge ofthe protector, such a lens curvature is not practical since it does nothave satisfactory optical properties in view of the large cylindricalerror present.

For some purposes, it may be necessary and it is believed to beadvisable to provide ventilating openings 1 in the frame 3. This may beaccomplished either when the frame is molded or after the article hasbeen molded by merely drilling a series of openings in the upper andlower portions of the frame. These openings serve to aid in theventilation of the inner surface of the lens 2 and prevent fogging.

In order to mount the protector when combined with a similar protectorfor the purpose of making a, pair, a pair of openings 9a are formed inthe nasal side of the frame through which a resilient cord or strap 9 isthreaded, held and arranged, in the manner illustrated, to form what isan adjustable bridge or attachment of a pair of protectors. Adjustmentcan be made by merely adjusting the bridge portion 3 of the cord orstrap to give greater or. lesser expanse as is required. Likewise, apair of openings Illa article has been molded.

The'type of rigid headband illustrated is of value in that. it provides.an inexpensive. structhis which can be conveniently adjusted withoutmuch effort and which is adequate for the pur-,, pose. of holding a.pair of protectors together in place on the head. Adjustment isaccomplished by merely sliding the material in the owning and thematerial is. held in place when positioned because of frictionalengagement. .The engagement is accentuated by the reverse direction ofthe. material in being threaded through the openings. w i

'Any lens used in aprotector must have sufficient thickness to.withstand the impacts of the objects which may be encountered inindustrial use. This. thickness usually is about 3 mm. and, as isapparent, is asource of prismatic error and of fatigue and irritation aswell as inconvenience if not. properly disposed in relation to: the eye.A means of correction for this .erroris to pro- Howevento provide such acurvature increases cylinder errorfor a'lens: of uniform thickness.

It is: the practice for prescription purposes to use certain insideand-outside curvatures and arrange them in relation to each other toprovide a lens of non-uniform thickness to reduce prism withoutincreasing cylinder error. Therefore, since in this invention it isdesired to provide a lens which is a protector and which hassubstantially desirable optical properties, it is necessary that theradius of curvature for outside surface 2a and the inside surface 21:have a certain relation and disposition with respect to the eye. It isdesirable if the optical center of the lens, assuming the lens is notconcentric, can be positioned, when the lens is placed in position,coincident with or substantially in alignment with the line ofstraight-ahead vision. With such an arrangement, the optical center ofthe lens inserved that, to change the optical center of the lens 20 ofthe protector I, represented by the line designated as AB, to a positionwhere the optical center is on the line AB coincident with the line ofstraight ahead vision, the nasal edge of the lens is moved towards theface engaging surface to such an extent that little space is availablefor a support. The lens 2|] is represented in dotted lines showing thereduction in the nasal wall, while the temporal wall is not fullyillustrated since it is obvious that the lens can be readily blendedinto the Wall shown for portion AB or that the lens can be disposedoutside the wall as shown and terminate likewise in a surface that willengage the face. The purpose of this illus-v tration is to show theadaptability of the integral lens and frame and to illustrate anadvantage in optical disposition. In the event that ,a separable eye cupor frame is used, it is practically impossible to provide a supportabout the nasal edge when the optical center is coincident with the lineof straight-ahead vision for a lens of about 58 mm. This particularradius is used to considerable extent because of the small curvature andlow cylinder error and its accommodation to the face, but difficulty isencountered in disposing the lens 2 so as to minimize prism error. Thebest attained prior to the invention is represented diagrammatically bythe line AB, while with my invention, prism is eliminated at the line ofstraight-ahead vision and is relatively low in the region of binocularvision. Also, due to the frame or support actually forming acontinuation of the lens due to its transparent nature,.much greatermonocul ar vision is attained. 'The lens can be positioned,illustratingadaptability, so that its edge actually forms a part of theface engaging surface. This would be an extreme condition of design, butfor some lens such may be necessary in order to provide a'properdisposition of the lens with respect to theeye.

Other modifications can be made of this invention such-as in the shapeof the frame that projects from the lens or in the shape of the lens andthe surfac of the frame that engages the face. However, the embodimentillustrated represents a preferred embodiment and provides advantageswhich are not obtainable in any construction of protector heretoforemade. According to the provisions of the patent statutes, I haveexplained now consider to represent its best embodiment.

However, I desire to have it understood that, within the scope of theappended claims, the invention may be practiced otherwise than asspecifically illustrated and described. a

. I claim: V

l. A one-piece eye protector of a molded transparent plastic and havinga horizontally curved lens to the edge of which a rearwardly projectingframe is integrally connected for spacing the lens from the eye, therear edge of the framebeing curved to fit snugly against the facearound'the eye, the temporal portion of the frame forming a transparentcontinuation of the lens with which it forms a small external angle, andsaid frame being formed to receive means for supporting the protector ineye-protecting position. a

2. A one-piece eye protector of a molded transparent plastic and havinga horizontally curved lens to the edge of which a rearwardly projectingan opening for receiving means for attaching the protector to the head.I

. HOWARD B. LEWIS

